Planooraph co



A. s. BALDWIN. SAFETY FUSE.

APPLICATION FILED DEC. I9. I9I?.

1,316,132. Patentedsept.1,1919.

. "nu f, 1.

.ARTHUR S. BALDWIN, OF BALTIMOREMARYLAND.

SAFETY-FUSE.

Specification of Letters atent.

Patented. Sept. 16, 1919.

Application filed December 19, 1917. Serial No. 207,891.

T 0 all 'whom 25 may concern:

Be it known that I, ARTHUR S. BALDWIN, citizen of the United States, residing at Baltimore, in the State of Maryland, have invented certain new and useful lmprovements in Safety-Fuses, of which the following is a specification.

This invention relates to improvements in safety fuses for shells or projectilesand has particular reference to that class of fuses in which the firing elements, including a plunger, are normally held in a safety or unarmed position, and upon the set-back due to the shock of ring the shell from a gun, the firing elements become armed so that when the shell strikes, the impact will cause the plunger to continue forward and thereby 'bring the explosive elements into operative contact to effect an explosion of the main charge.

The presentinvention has particular reference to improvements in that form of safety fuses in which the plunger parts are normally held separated, or in the unarmed condition, by means of a shear device which device becomes ruptured or sheared, upon the shock of firing, to allow the parts to shift to an armed position.

It has been found in the actual practice that shells or projectiles are subjected to suiiiciently rough handling in shipment or in transportation over rough roads to cause the numerous vibrations and jars to rupture or partially rupture the shear devices in the fuses before the shells arrive at the point of use, and that the partial or complete rupture of the shear means places the fuses thereof in a condition that is dangerous to handle in unloading at their destinations and then again when loaded into aI gun.

The object therefore of my invention is to provide improved means to take the numerous ordinary vibrations and jars from the shear means during transportation and handling and thereby prevent partial or complete shearing', so that if the shell should be accidentally dropped or subjected to an unusual jar or shock, prior to actual firing, the shear means will be in condition toperform the work for which it was intended and be of sufficient strength to prevent arming of the plunger parts.

The invention is illustrated in the accompanying drawing in which,-

Figure 1, shows the improvedy fuse 1n vertical longitudinal section.

Fig. 2,y illustrates a cross-sectional detail through the fuse,-the section being taken on the line 2-2 of Fig. 1.

Fig. 3, shows a cross-sectional detail through the plunger parts of the fuse, as the same would appear if taken on the line 3 3 of Fig. 1, and

Fig. 4,.. shows a longitudinal section through the fuse on a line at right angles to the section in Fig. 1, and illustrates the parts in the armed condition.

In illustrating my improvement I have elected to show the same in connection with the fuse device set forth in U. S. Letters Patent 1,239,248 granted to me September 4th 1917.

Referring to the drawing, the numeral 5, designates the case or stock which is provided with an interior 4circular cavity or chamber 6, and eXterior-screw-threads 7 by means of which it may be screwed into a shell in the well-known manner.

In the present instance the inner end of the fuse stock isl closed by a cap or plug 8, in which is located one ofthe firing elements, such for example as the primer 9, which latter, when detonated will re the main charge in the shell.

A plunger body 10, is located in the cavity 6, of the fuse stock and has a lower central passage 11, and upper central passage 12, of a somewhat lesser diameter than the lower passage. Between the two passages, the plunger body is provided with an annular groove 13, of a greater diameter Athan either of said passages and said groovev is located around and directly under the upper smaller passage 12.

Directly over, and around the lower passage 11, the plunger-body 1s provided with a recess 14, which in the present instance, 1s annular in form and is of a greater diameter than said lower passage 11.

Between the annular groove 13, and the recess .14, the interior of the plunger-body has an annular portion 15, which is of less diameter than the groovek whereby to form a shoulder 16, around the lower side of the groove. The annular portion 15, and the lower` passage 11, in the present instance are of substantially the same diameter, for reasons presently to be explained.

' By means of the arrangement of grooves and recesses in the plunger-body as abovedescribed an overhanging shoulder 17 anda shear-ing edge 18, are

formed around the base of the upper. central passage 12, while a shoulder 19, is produced immediately above and around the upper end of the lower central passage 1l, all for purposes presently to be explained.

In the present instance I also provide the plunger-body with a recess 20, whichl extends substantially in a longitudinal direction therein and whose lower end opens into the interior of the plunger-body below the annular groove 13, also for a purpose that will presently be explained.

The interior of the plunger-bodyis formed as above described for the purpose of re-V ceiving an explosive element, which in this instance is the firing pin structure.

In the art to which this invention relates it is common to arrange a primer that may be moved toward a relatively stationary firing pin, or, to have the primer the stationary element and arrange the iiring pin so it may plunge forward against the primer. I have here shown and described the latter form of fuse structure, but it is to be understood that the expression, explosive element, hereinafter referred to s to be construed as meaning one or the other of the two elements, the pin, or the primer, without regard to whether the pin or the primer 1s the movable element.

lVith the above understanding in view the element inclosed by the plunger-body comprises a body whose lower end 2l, is of a diameter to freely enter the lower passage l1, of the plunger-body and whose upper end 22, is of a smaller diameter and freely enters the upper central passage 12. In this instance the upper smaller end 22, carries a ring pin 23, on its extreme end that projects toward the inner end of the smaller passage l2, and also toward the primer 9.

The smaller end 22, is also provided with a shear pin 24, which extends diametrically through said end and has its two ends 25, projecting in a plane beneath the shoulder 17, on the plunger body. These projecting ends 25, normally terminate at the wall of the annular portion 15, and the upper circumferential side of the pin-ends 25, are slightly below the shoulder 17, instead of being in contact therewith.

At the base of the smaller end 22, the body is provided with an annular groove or undercut 26, and this groove has position directly on top of an annular shoulder or anvil 27 which is formed by the larger lower end 21. By referring to Fig. l, of the drawing it will be seen that the shoulder or anvil 27 is directly beneath, but normally spaced from the overhanging shoulder 17, on -the plunger-body so that if the plungerbody were lowered, its shoulder 17, would l act as a hammer on the anvil 27,-the shearpin 24, however when in place, prevents any possible telescoping of the two bodies, under accidental shocks, less than that caused by the set-back which takes place when the shell is fired from a gun.

It has been pointed out that the shear-pin ends 25, are located slightly below the plunger-body shoulder 17 and this is important to the present invention because it is desirable to prevent the slight vibrations of the plunger-body, during transportation over rough roads, from being` delivered onto the shear pin ends and gradually weakening or cutting through said ends, so that if by accident a greater shock or jar is delivered by the plunger-body prior to actual firing from a gun, said pin-ends will be sufciently strong to withstand it, and not permit the pin-ends to rupture and allow the fuse to become armed accidentally.

In order to relieve the pin-ends from possible damage by reason of the vibration of the plunger-body, during transportation, or handling, I provide a yielding means which I interpose between the plunger parts, that is, between the two bodies 10, 2l and 22, so as to act as a shock absorber and keep the shoulder 17 of the plunger-body from striking the projecting ends 25, of the shear pin, unless the shell with the fuse therein is accidentally subjected to a considerable shock, such as would be occasioned by dropping the shell, and which would be of sufficient force to overcome the force of the yielding means.

In the present instance the yielding means employed consists of a spiral spring 28, one end of which extends up into the plungerbody recess 20, and the other end of which seats on the annular shoulder or anvil 27, so as to yieldingly press the two bodies in opposite directions and keep the plungerbody shoulders 17 in spaced relation with respect to the shear pin ends 25.

It will therefore be understood that the two bodies, 10, 21-22, are held in an extreme separated position by the yielding means, the spring 28, and that the shear-pin ends 25, are normally free from contact with the plunger-body `and therefore perform no function under ordinary vibrations,-jars or slight shocks and consequently are free from liability of damage or partial rupture that might take place if the shoulder 17, and shear edge 18, of the plunger-body were vibrating and hammering on said pin ends. The result of this, is that the shear-pin ends will be maintained in good condition and will be able to withstand a blow of thel plunger-body shoulder, that might result through accident, and the plunger-parts will thereby be maintained in a safety or unarmed condition, until subjected to the tremendous shock upon projecting the shell from a gun, when the yielding means will give, and the pin-ends 25, will be sheared completely off by the shear edge 18, of the plunger-body.

When a shell containing the fuse is fired or projected from a. gun the yielding means 20, will readily give, andv the ltendency of the plunger-body to remain still while the body 21-22,k drives forward with the stock, enables a clean shearing action of the fpin ends 25, to take place because there 'will be a movement between the pin-ends and l'plunger-body shear edge 18, before those parts come together. This shearing faction 'completely cuts olf the two ends 25, of the shear pin and allows the shoulders 17 and 27 to move, one toward the other and in doing so, hammer the two sheared o ends like a rivet, 31, spreading the metal of said ends on the shoulders 17 and 27, until it enters the two grooves 13 and 26, thereby riveting the two bodies 10, 21-22, into locked engagement as shown in Fig. 4 of the drawing and holding the spring 20, compressed in the recess 20, of the plunger-body.

The enlarged portion 21, of the inner or, in this instance the firing-pin body, is provided with arecess 29, which opens at one side and extends diametrically in the body.

A bolt 80, is placed in this recess 29, and is normally held therein by the lower end of the plunger-body extending down across the outer end of the recess, as shown in Fig. 1.

When the set-back takes place however, andthe plunger part-s are shifted to the positions shown in Fig. 4, of the drawing, the bolt 30, will have 4position in register with the recess 14, in the plunger-body and as the shell is rotated upon leaving the gun, the centrifugal action causes the bolt to move outwardly into the recess, as shown in Fig. 4, and thereby provide an additional lock between the plunger-body and the firing-pin body which will become 'eifective in case the riveted ends 31, sheared from the shear-pin, fail to do the locking as they should.

Having described my invention, what I claim is 1. In a fuse device the combination with a stock having a chamber therein, of two bodies in said chamber; means for yieldingly holding the two bodies at opposite ends of the stock-chamber, and a shear device in the path of one of said bodies and engaged by the latter after the holding means has yielded to a predetermined extent.

2. In a fuse device the combination with a stock having a chamber therein, of two bodies having telescopic relation and in said chamber; means for yieldingly holding the two bodies in separated relation, and shear means engaged by one of said bodies after a predetermined yielding movement has been made.

3. In a fuse device the combination with a stock having a chamber therein, of two bodies in said chamber and havingV ytelescopie relation one with the other; a shear device carried by one of said bodies and projecting in the path of the other body but 'spaced from the latter, and means for yi'eldingly holding the two bodies to keep 'the 'shear device of 'the lone from engagingv the other during `ordinary handling and transportation. v y

4. In a fuse device the 'combination 'with a stock having a chamber therein, of two bodies in said chamber and each body havi ing a shoulder projecting in a direction t'oward the other whereby the shoulder may have 'a 1ap'p'ed relation; a shear ldevice in a y"plane between said shoulders, and yielding means for maintaining a separation of at least one shoulder from the shear devices.

5. In a fuse device the combination with a stock having a chamber therein, of a plunger-body in said chamber said body having a longitudinal passage with a shoulder therein; another body in said chamber and entering the longitudinal passage of the plunger-body and said other body also having a shoulder; a shear device carried by one of said bodies and projecting between but spaced from both of said shoulders, and yielding means for pressing the two bodies in onoosite directions.

6. In a fuse device the combination with a stock having a chamber therein, of a plungerbody in said chamber said body having a. longitudinal passage with a shoulder therein; another body in said chamber and entering the longitudinal passage of the plungerbody and said other body also having a shoulder; a shear device carried by one of said bodies and projecting between but spaced from both of said shoulders, and a coiled spring having one end seated on the shoulder of said other body and its other end pressing against the plunger-body to keep the plunger-body shoulder from engaging the shear device.

7. In a fuse device the combination with a stock having a chamber therein, of a plunger-body in said chamber and having a central passage with a shoulder therein and also provided with a recess at one side of said passage; a second body in said chamber and entering the central passage of the plunger-body said Second body also having a shoulder; a shear device carried by one of said bodies and projecting toward the other body between said two shoulders, and a coiled spring seated against the second body and .entering the recess of the plunger-body.

8. In a fuse device the combination with a stock having a chamber therein, of a plunger-body in said chamber and having two passages one with a larger diameter than the other and forming a shoulder between said passages; another body in the chamber and having one end of a diameter to enter the smaller of said plunger-passages .and the other end of a diameter to enter the larger of said passages; a. shear device earrled by one of said bodies and projecting toward the other,said shear device being vinterposed between but spaced from the smaller plunger-passage and the largest end of said other body and yielding` means for pressing the two bodies in opposite directions.

9. In a fuse device the combination with a steek having a Chamber therein, of tvvo ARTHUR S. BALDVIN.

Copies of this patent may be obtained for ve cents each, by addressing' the Commissioner of Patents. Washington, D. C. 

